A cost-effective method to maintain sugar acid neutralization during a sugar decarboxylation process is described in U.S. Patent Application No. 61/777,890. Therein, the sugar acids can be decarboxylated to produce carbohydrate aldehydes at the anode of a two-compartment electrolytic cell, which can be divided by a cation exchange membrane. A hydroxide salt is produced in the catholyte. Neutralization of sugar acid solutions is maintained by back migration of hydroxide from the catholyte to the anolyte and by the addition of hydroxide from the catholyte to the anolyte.
The electrolytic reduction of sugar aldehydes has been employed in the production of sorbitol, xylitol and mannitol, as in U.S. Pat. Nos. 2,303,210, 2,507,973, and 2,537,304.
Electrolytic cells can be constructed in many different configurations. However, all previously disclosed examples of carbohydrate acid electrolytic decarboxylations and carbohydrate aldehyde reductions are carried out in either single- or double-compartment cells.
The aldehyde functionality of carbohydrate aldehydes are often reduced to alcohols to produce products of greater value. There remains a need for cost-effective methods to reduce or eliminate such a processing step.